Welcome

First of all, may I welcome you to my site. My name is Chris and I'm from the UK and work as a Systems Engineer for Cisco. This blog was initially created to post up my subnetting technique but has now got more stuff to do with attaining Cisco certifications. Either way I really hope that the content is sufficent for your needs and I look forward to hearing your feedback. If you find that the content really helps you please feel free to donate using the PayPal link on the right.

Here we'll try to authenticate a session between two routers. One side of the router will use RADIUS while the other will use TACACS+. The side using RADIUS will be configured using a AAA server group. The TACACS+ server will be globally configured. Both RADIUS and TACACS+ use "cisco" as the password.

Router 1

1. Configure a new AAA model

aaa new-model

2. By default, the "aaa new-model" command will require local authentication on the console port. To override this, and save us from locking ourselves out, we must configure specific console authentication and the easiest way to do that is by using "none".

4. Configure AAA to authenticate PPP sessions against the RADIUS server group and if that fails it should try the local database.

aaa authentication ppp PPP_AUTH group MY_RADIUS_GROUP local

5. Configure the phyiscal interface to use the AAA authentication session

interface s0/0 ppp authentication PPP_AUTH

Router 2

1. Configure a new AAA model

aaa new-model

2. By default, the "aaa new-model" command will require local authentication on the console port. To override this, and save us from locking ourselves out, we must configure specific console authentication and the easiest way to do that is by using "none".

I've already posted about route summarization but I found this interesting technique for calculating complex route summaries at http://w...

Customer Feedback

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Thanks so much for not only the tip, but the detailed tutorial on how to setup and actually use GNS3. This is completely invaluable information."Brad, GNS3 Configuration Guide comments

"Hi, just tested it.It's very incredible, perfect.Good work, if you have some tips for CCNA please post.I use GNS3 and DynamipsGreaaaaaaaaaaaat"Fayda, GNS3 Configuration Guide comments"Chris,I just visited your blog and I want to congratulate you on your effort. Guys, I recommend this subnetting tutorial."Forum Admin, www.how2pass.com"I wanted to thank the original poster for this information....reading this finally made it click and solved the mystery of subnetting for me and was instrumental in passing the CCNA yesterday."via Cisco Forum

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